摘要：Horizontal well staged fracturing technology is a key technology to improve oil and gas recovery in unconventional reservoirs. In this paper, taking the tight sandstone reservoirs of the Yanchang For-mation in the western Ordos Basin as an example, numerical simulation of fracturing is used to study the coupling relationship between fractures and stress in tight oil horizontal wells. The research results show that the horizontal well fracturing in the study area adopts hydraulic sandblasting perfo-ration + annulus sand adding staged fracturing technology.4 clusters is the number of clusters with the least interference. The lower the average sand ratio, the greater the liquid consumption, and the longer the half length of the main fracture. The lower the average sand ratio, the easier the proppant is transported to the deep part of the fracture. Con-sidering the effects of fracture length(<240 m) and fracture width, the average sand ratio is optimized to 20%. During the construction process, the dy-namic fracture width with a displacement of 8 m²/min is the largest， which is conducive to the construction of the main fracture fracturing under the influence of multiple fractures. When the hori-zontal well trajectory is consistent with the hori-zontal minimum principal stress direction, the stress value is the smallest when the fracture dip is 30°~70°.At this time, the formation is not easy to rupture, and the fracturing effect is relatively poor. The development zone of near-horizontal fractures and high-angle fractures has a better fracturing ef-fect on horizontal wells, and the fractured formation is more likely to rupture and form an effective net-work of fractures. When the fracture strike is in the range of0°-50°,the stress value is low,and the rock near the well is not prone to rupture, which is un-favorable for horizontal well fracturing. When the fracture strike is in the range of 50°~90°, the stress value is low, and the rock near the well is prone to rupture, which is beneficial to horizontal well frac-turing.
